Head-clamping mechanism.



Patented Jan. 31, 1911.

2 SHEETSSHBET 1.

G. L. GROHMANN.

HEAD GLAMPING MEUHANISM.

APPLICATION FILED DEC. 7, 1908. 93,225,

C. L. GROHMANN.

HEAD CLAMPING MECHANISM.

APPLICATION FILED DEC. 7, 1908.

Patented Jan.31, 1911.

2 SHEETSSHEET 2.

In men for: 6L5. Grohznann fly lzl's' Aforn e95;

sra'rns Parana CARL L. GROHMANN, Oh HARTFORD, CONNEGTICUT ASSIGNOR T0 PRATT & WHITNEY COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF NEW JERSEY.

HEAD-CLAMPING MECHANISM.

Specification of Letters Patent.

Application filed December 7, 1908. Serial No. 466,273.

To all whom it may concern:

Be it known that I, CARL L. GROHMANN, a citizen of the United states residing at Hartford, in the county. of Hartford and State of Connecticut, have invented certain new and useful Improvements in Head- Clamping-Mechanism, of which the following is a specification.

This invention relates to head. clamping mechanism and one of the primary purposes of the invention is to provide simple mechanism of the kind set fort h for solidly and substantially holding a head or analogous part in an adjusted position and for also causing positively the simultaneous setting of a plurality of clamps from an actuatpr I common to said clamps. I

In the drawlngs accompanylng and form-.

ing part of the present specification I illustrate in detail several forms of embodiments of the invention which to enable those skilled in the artto practice said invention vwill be fully set forth in the following description while the novelty of the invention will be included in, the claims succeeding said'description.

Referring to said drawings, Figure 1 is a front elevation of head clamping mechanism comprising my invention. Fig. 2 is a horizontal section on the line 22 of Fig. 1.

v Fig. 3 is a detail view of a clamp and certain adjunctive devices together with a portion of the head. Figs. 4. 5 and 6 are news corresponding substantially to Fig. 2 and each illustrates a modification although in said Fig. 5 only one side of the head and the devices thereat are shown. Fig. 7 is a side elevation of a still further modification, apd, Fig. 8 is aface view of the same.

Like characters refer to like parts throughout the several figures. v i There are in certain types of the machines to which allusion has been made, a column or similar support and a head or equivalent member movable thereon. It is assumed that the part 2 is such a column and that the part 3 is such a head. The head need not travel "ertically in which event it would not be. strictly speaking. sustained by a column. Said head 3 serves as a suitable carrier for a tool (not shown). The tool-spindle is illustrated, being denoted in a general way by rier for the work.

of these screws. lng screws 7 there is a screw as 8 WlllCl'l does The head 3. is supported by suitable ways or guides upon the column or support which are quite common in the machines to which I have'referred and for this'reason and for the further one that the same form no part of the present invention it is needless to describe them in detail.

The clamping mechanism preferably though not necessarily includes twdclamping devices which may be made in several different ways but which advantageously Patented Jan. 31, rent."

consist of gibs. The gibs or clamping devices illustrated are denoted by 5' and 6 respectively and advantageously they have at all times a sliding contact or engagementwith theicolumn or support 2, their inner or active surfaces bearing against what is represented as the rear side or surface of said column. The head therefore when the gibs or clamping devices are in their inoperative positions can be readily raised and lowered. The gibs are connected to the head preferably in some positive but removable manner and several Screws all of which are denoted by Z satisfactorily answer such purpose. There may be any desired number In addition to the attachnot serve such function but which performs a different otficeas will hereinafter more particularly appear. The clamping devices or gibs 5 and Goverhang or overlap the support or column 2 and itwill be evident that when they are strained or drawn into firm engagement with the said column'the head will be held against movement in opposite directions. Preferably those portions of the sides of the head 3 opposite the screws 8 are rabbeted or cutaway as at 9 which permits a flexing or bending of the clamping devices or gibs when pressure is applied thereto, to clamp the head. These rabbets or cut-away portions are exaggerated in the drawings; in practice'they are, hardly perceptible and it is possible that there are cases where their presence will not be necessary.

As will hereinafter appear I provide in connection with a pair of clamping devices of whatever character they may be; an actuator common to them both and means for transferring the effect of said actuator,

which is usually manually-operable, to said clamping devices in unison the result being that the head can be quickly clamped in an adjusted position. Preferably the means which simultaneously operates said clamping devices applies to them equal or uniform pressures so that the head will be held in such a steady, stable manner that there is no.

possibility of chattering-due to wabbling of the head. The said ibs or clamping devices are also substantial y coextensive with or practically equal in length the height of the head so that when said clamping devices are in their releasing position they aid in accurately guiding the said head up and down.

The actuator for the two gibs or clamping devices may take several forms; that shown is denoted by 10 and consists of an arm or crank cobperative in some suitable manner preferably with a rod or shaft as 11 extending depthwise or from front to rear of the head. As will hereinafter appear this rod or shaft constitutes part of the means for transferring the effect of such actuator simultaneously to the two clamping devices or gibs 5 and 6. It will be seen that the actuator is shown as located at the front of the head so as to be easily and readily accessible to the attendant of the machine equipped ,with said head. lVhen therefore it is necessary for ,ciprocatory movement although the same is.

such attendant either to clamp or release the head it is not necessary for him to walk back of the head or reach therearound to accomplish the results in question. It is quite common to provide separately operated clamping devices for a machine head and it frequently happensthat the attendant will only set one of said clamping devices from forgetfulness or other causes; in such an event vibration of the head naturally follows and the consequence is an inferior grade of product. I eliminate such a possibilty by" the present mechanism.

The rod or shaft 11 has an endwise or revery slight and this action is accomplished by the actuator 10 which acts against the tail of said rod. The actuator 10 is shown as having a shank 10' threaded into a nut as 12 fixed, for example by threading in the outer end of the bore 13 in which said rod or shaft 11 is located. It therefore follows that when the actuator 10 is turned to the right its shank 10 is fed inward so as to impart an advancing movementor inward thrust to said rod 11. On the opposite mo tion of the actuator the rod can be backed to its original position. I prefer to employ said rod 11 for operating rod means and a cam action for this purpose is quite satisfactory. Said rod means is shown as consisting of two rods or bars as 14 and 15 extending transversely of the head 3. I use the expression rod means in a broad sense to include one or more rods. Said-rods 14 and 15' when operated by the rod 11 set simultaneously the two clamping members or gibs 5 and 6. The rod serves as a suitable wear-compensating element and' owing to its presence acts as a means for applying definite pressures to the respective clamping devices whether said pressures be equal as is so in the present case, or otherwise. Said rod 11 acts as a spreader or expander for oppositely thrusting or separating the two rods 14 and 15 and it is in the nature of a float; in that it is bodilyv movable for as will be clear it can in addition to its endwise or longitudinal movement also have alateral motion the latter being due to the fact that it is smaller in size than the bore or passage 13. This lateral movement of said rod is what may be utilized to compensate for wear in any of the parts by reason of which I can also set the clamping devices with the predetermined or definite pressures and can also set said clamping devices absolutely in unison or simultaneously.

The rod 11 is shown as having at its inner end or head two cam or wedge-faces 16 and 17 respectively which are shown .as converging inwardly and which act against angular faces on the butts of said rods 14 and 15. When therefore the rod 11 is advanced by the actuator 10 it will simultaneously thrust said rods 14 and 15 outwardly and op- I positely and owing to the fact that said rod 11 is fioatable in its mounting I insure absolutely the simultaneous setting of the two clamping devices 5 and 6 notwithstanding the fact that there may be wear in .anyof the parts. The rod 11 amply compensates for such wear wherever it may be between the actuator and the said clampingdevices It will be clear that the bolts or screws 8 are free of the head or carrier 3; that is theyhave no direct connection therewith in the sense that the gib attaching screws or bolts 7 have, Said screws 8 are represented as tapped into plugs as 18 endwise movable'in bores or ope'nings.'extending depthwise of the head 3 and which open into the rabbets 9. It is therefore evident that these plugs constitute a simple means forbending or flexing the gibs or clamping devices 5 and 6 at points opposite said rabbets by virtue of which said gibs can bedrawn into clamping relation with said column or support 2. The rods 14 and 15 serve as a convenient and simple means for setting the two clamping devices through the intervention of said plugs during which action the latter are drawn forward. The head ends of said rods 14 and 15 are shown as being of cone form as at 19 and are adapted to enter similarly-shapedcounterbores or seats as 20 in the outer ends of said plugs said cone heads acting as Wlll be evident as cams. While the shape of that of saidcone heads the former are much the'plugs can be advanced to set'the gibs or clamping devices without possibility of said counterbores is thesame as larger than the latter by reason of which in their unclamped positions as shown in the several figures of the drawings and that it is desired to hold the head 3 in .an ad-.

justed position. To accomplish .this the actuator 10 is swung down or turned to the right. When the actuator 10 is thus operated its shank 10 imparts an inward or forward thrust tothe rod 11 and the latter in turn spreads. the rods 14 and 15 the cam or cone heads of the latter drawing forward the two plugs 18 and setting the two clamping devices or gibs 5 and 6. It will be seen that said clamping devices 5 and 6 have at all times a sliding fit with the column 2 and that they are substantially coextensive with said head. These relations, however, are in no wise essential. At this point it will be evident that the foregoingv description applies to Figs. 1 to 3 inclusive. Hereinafter I describe certain modifications wherein the clamping dev1ces are not in the form, strictly speaking of gibs and wherein said clamping devices cover but a very small portion of the column. It is possible that they might when set simply have a knife-edge bearing against the column or any other similar part the extent of their hearing not being a matter of great importance.

ll will first describe the construction shown in Fig. 4. In this view the column is denoted by 2 and the head by '3 and these two parts are precisely like the similar members hereinbefore described. The gibs are desig nated by 5 and 6 and they are connected to plugs 18 by screws 8 which all are like the previously described parts. Extending between said plugs 18 is a rod 21 represented as provided at one end with a stationary collar 22 provided with a tapered active portion 23 m freely fit an opening'or seat 24 of substantially similar formation. 1 have shown as loosely mounted on said rod a second collar 25 also having a tapered portion 26 to freely fit a similarly shaped-opening 27 It shouldbe stated that the opening 24 is in the plug 18 shown on the right in said Fig. 4 while the opening 27 is in the other plug. 1 have shown as threaded to the end of the 'rod 21 adjacent the slidable or loose collar 25, a handle 28 located exteriorly to. said collar and adapted to engage said collar 25. It will be clear that when the handle or arm 28 is turned. the collar 25 will be thrust toward the right in Fig. 4; while the collar 22 .will be pulled toward the left insaid figure in view of the similar pull on said rod. In other words the two collars are caused to approach each other the consequence being that the. plugs 18 are drawn forward to simultaneously set the two clamps or gibs 5 andv 6 Referring now to Fig. 5, 2 and 3 denote the column and head respectively. 6 shows the gib which is perforated to receive the plug 18 provided with a head 18 for engaging the outer surface of'the said gib or clamping member 6*. A rod 21* is provided with a head 22 having a tapered portion 23 to fit the substantiallysimilarly shaped seat- 124 in said plug 18". This collar 22 is fixed to the rod 21 and operates precisely likethe collar 22-. Vhen therefore the collar 22 is moved to the left in Fig. 5 the plug 18 is drawn forward and the head 18 pressesthe clamp or gib 6 firmly against the column 2". There is at the other side of the column and head a plug 18 operable by devices such as those shown at the left in said Fig. 4 whereby said two plugs '18 can be set absolutely together andnot one in advance of the other.

In Fig. 6 I show a construction wherein the clamps for holding the head in an adjusted position are not in the form of gibs strictly speaking but are simply the heads 18 of plugs as 18? which are the counterspecificallydescribed; The plug'lS on the rightin Fig. 6 is shown as having an opening as of tapered form to receive t-hesimilarly shaped portion 23 of the head or collar 22 of the rod 21 against the free or outer endof which the. tip of the screw 28 is shown as bearing, said screw being threaded through a collar or nut 25 provided with a tapered portion 26? at its outerend to fit the 18 on the left in said-Fig 6. The screw or threaded stem 28* extends entirely through the collar ornut 25 and is represented as provided with a handle 28". It follows therefore that when this handle is turned in the proper direction the collars 22 and 25 are moved outwardly and oppositely so that the tapered portions 23 and 26 by acting against the plugs 18 can simultaneously set the heads 18 of said plugs into clamping engagement with the column 2 so as to hold the head 3 in adjusted relation thereon.

In Figs. 7 and 8 I show a construction whereina divided gib 5 may be employed. Thisgib unlike the gibs previously described does not clamp the head. It is shown in two sections which are respectively connected to said head in some rigid manner, for example by means of screws as hereinbefore' set forth .Between the sections of said gib 5 is a clamp or jaw 5 which is adapted to engage the column although such latter part is not illustrated in either of said two last mentioned figures. This clamp or jaw 5 is perforated to receive the screw 8 which is tapped into a plug I as 1S which may be constructed and operparts otherwise of the plugs hereinbefore' similarly shaped opening 26 in the lug I I atcpre cisely like the plugs hereinbefore described. When the plugs 18 are drawn forward the clamps or jaws 5 are set into clamping relation but the gib sections at opposite sides of said clamps are not operated although they may have a sliding connection with the column as previously stated. a

In the several forms of the invention I provide a movable head and its support, a

pair of clamps for clamping said head in an adjusted position, an actuator common to both clamps, and means for transferring the efl'ect of said actuator to both clamps and for, positively preventing the setting of one clamp in advance of the other by virtue of which it is possible to always set said clamps absolutely in unison which is a verv advantageous feature in that there is impossibility of the head being subjected That I claim is: a 1. The combination of a'column, a head slidable on said column and having bores extending from front to rear thereof, plugs endwise slidable in said bores and having clamping devices for engaging said column and devicesvfor operating said plugs to set said clamping devices, the plugs having tapered counterbores to receive said operating devices. i 2. The'combination of a column, a head slidable vertically of said column and having bores extending from front to rear thereof, plugs slidable in saidbores, provided with clamping devices for engaging ,said column and also having tapered counterbores,

rods extending crosswise of the head, provided with tapered outer ends to engage in said counterbores, a third rod provided with an angular head to engage between the ends of said first mentioned rods, and 'movable in all directions, and a hand operable screw tapped into said head and adapted to advance said third rod.

In testimony whereof I aifix my signature in presence of two witnesses.

CAR-L L. GROHMANN. lVitnessesr W. M. STORRS, H. W. KILBOURNEE. 

